It definitely depends. For example, the Blade Runner blu-ray is phenomenal. The Road Warrior blu-ray is very good when compared to the standard version. I also bought Full Metal Jacket on blu-ray and it was good, but nothing to write home about. So I think it really depends on how much care they put into the restoration. But yeah, newer films are gonna look way better since they were shot with the intension to go to an HD format anyway.
Still, I find that the PS3 does an excellent job upconverting standard DVDs. My Lord of The Rings box set still looks awesome.
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